FAS2020 Install

I recently purchased a FAS2020 with 450 GB disk. The system is currently setup in an Active/Active Cluster with 7 disk (1 spare) on Controller 1 and 3 disk (1 spare) on Controller 2. Now originally I had planned to have 2 TB of space for e-mail storage, however it seems as though I was wrong. Controller 1 has a total of 1.7 TB and Controller 2 has a total of 349 GB.

The systems volumes are currently setup as displayed below:

Controller 1:

Aggr0 (1.7 TB) [52% used]

vol0 (Capacity: 50 GB Total Size: 62.5 GB) Root

VFMS_1 (Capacity: 387 GB Total Size: 430 GB) VM Boot Drives

VFMS_2 (Capacity: 369 GB Total Size: 410 GB) VM Data Drives

Controller 2:

Aggr0 (349 GB) [100% used]

vol0 (Capacity: 50 GB Total Size: 62.5 GB) Root

CIFS_1 (Capacity: 36 GB Total Size: 45 GB) CIFS Shares

VFMS_3 ( Capacity: 200 GB Total Size: 235 GB) VM Boot Drives

On Controller 1 I have 835GB of free space for future expansion of my VM Data Drives.

So my question is, why does Controller 2 receive only 349 GB of useable space? The 450 GB drives have a formatted capacity of 410 GB, so I would have assumed I would get at least that much. It seems like an awful waste of 4 drives to get only 349 GB for use.